With the rapid development and continuous innovation in the lighting industry, and the growing importance of energy savings and environmental protection, light-emitting diode (LED) based lighting has rapidly developed as a revolutionary lighting technology. However, the luminance of LED associated with the parameter of luminance intensity is in direct proportion with the current and forward voltage drop of the LED, and also varies with external temperature. Therefore, it is very important to select a substantially constant current generator to drive the LED lighting, and to maintain ideal luminance. The full advantages of LED lighting can only be achieved with optimum performance of the associated LED driver.